Insulation performance monitoring device for large-scale generator

Abstract

The utility model discloses a large generator insulation performance monitoring device which comprises a power supply protection module, a lightning protection module, an ACDC power supply module, an insulation monitoring module, a communication module and a safety module. The input end of the power supply protection module is connected to the output end of an external alternating current power supply, the output end of the power supply protection module is connected to the input end of the lightning protection module, and the output end of the lightning protection module is connected to the input end of the ACDC power supply module and the power supply end of the insulation monitoring module; the output end of the ACDC power supply module is connected to the power supply end of the communication module, the monitoring signal output end of the insulation monitoring module is connected to the monitoring signal input end of the communication module, and the fuse module is arranged on a line of the monitoring signal input end of the insulation monitoring module. The problem that an online monitoring technology and an offline measurement mode in the prior art cannot meet the requirement for monitoring the insulation condition of the generator is solved.

Description

Technical Field

[0001] This application belongs to the technical field of generator insulation performance monitoring, and specifically relates to a large generator insulation performance monitoring device. Background Art

[0002] As the core component of a generator set, the stable operation of a large generator is crucial for the economic benefits of the unit. Among them, insulation faults constitute one of the main challenges faced by generators. Given that large generators need to withstand the combined effects of complex electrical, thermal, mechanical, and environmental stresses during operation, these factors directly accelerate the degradation process of winding insulation. The decline in insulation performance not only weakens the long-term stable operation ability of the generator but may also induce operating faults, and in extreme cases, even lead to sudden shutdowns, seriously affecting production safety.

[0003] When monitoring the insulation condition of a generator, insulation resistance measurement, as a long-established and easy-to-implement method, has been widely used to evaluate the health status of electrical insulation. This method can effectively reflect the moisture content, conductivity defects, and surface leakage of the generator insulation. However, the traditional off-line measurement method relies on manual use of a megohmmeter to access the generator circuit for detection, which has problems such as low efficiency, limited accuracy, and high safety risks. Especially for remote or offshore generator sets, the implementation difficulty is significantly increased.

[0004] Currently, on-line monitoring technology has been gradually promoted. This technology integrates an insulation monitor and its supporting system into the generator circuit to achieve automatic insulation detection during generator shutdown. Once poor insulation performance is detected, an alarm signal can be remotely triggered. Although on-line measurement provides many conveniences, the existing systems still have deficiencies:

[0005] 1. Single function: Most monitoring devices can only detect a certain insulation parameter and lack the ability to comprehensively analyze the insulation state (such as partial discharge, dielectric loss factor, etc.).

[0006] 2. Limited detection comprehensiveness: It is unable to cover multiple key insulation technical parameters simultaneously, affecting the comprehensiveness and accuracy of fault diagnosis.

[0007] In contrast, although the off-line measurement method has its inherent advantages, such as the ability to visually inspect specific areas, its disadvantages are also obvious:

[0008] 1. Low efficiency: The entire process from preparation to completion of detection takes a long time, affecting the maintenance efficiency.

[0009] 2. Precision fluctuation: The accuracy of the detection results highly depends on the performance of the megohmmeter and the skill level of the operator.

[0010] 3. Difficult to promote: Professional technicians are required for on-site operation, making it difficult to quickly deploy on a large scale.

[0011] 4. Lag in data processing: Data recording and processing rely on manual labor, unable to achieve instant feedback, affecting the timeliness of fault prevention.

[0012] 5. High cost and risks: The cost of manual detection is high, and at the same time, the operators face certain safety risks. Summary of the Utility Model

[0013] By providing a monitoring device for the insulation performance of large generators in the embodiments of the present application, the problem that neither the existing online monitoring technology nor the offline measurement method can meet the monitoring requirements of the insulation condition of generators is solved.

[0014] To achieve the above object, the embodiments of the present utility model provide a monitoring device for the insulation performance of large generators, including a power supply protection module, a lightning protection module, an AC-DC power supply module, an insulation monitoring module, a communication module, and an insurance module;

[0015] The input end of the power supply protection module is connected to the output end of an external AC power supply, the output end of the power supply protection module is connected to the input end of the lightning protection module, and the output end of the lightning protection module is connected to the input end of the AC-DC power supply module and the power supply end of the insulation monitoring module;

[0016] The output end of the AC-DC power supply module is connected to the power supply end of the communication module, the monitoring signal output end of the insulation monitoring module is connected to the monitoring signal input end of the communication module, and the insurance module is arranged on the line of the monitoring signal input end of the insulation monitoring module.

[0017] In a possible implementation manner, an indication module connected to the insulation monitoring module is further included.

[0018] In a possible implementation manner, a cabinet is further included, the cabinet includes a cabinet body and a cabinet door connected to each other, and a lock body is arranged on the cabinet door;

[0019] An installation bottom plate is arranged at the bottom inside the cabinet body, and guide rails are arranged on the installation bottom plate;

[0020] The power supply protection module, the lightning protection module, the AC-DC power supply module, the insulation monitoring module, the communication module, and the insurance module are all installed on the guide rails through buckles, and the indication module is installed on the outer wall of the cabinet body.

[0021] In a possible implementation manner, a power interface, a communication interface, and a test interface are arranged on the side wall of the cabinet body;

[0022] The power interface is connected to the input end of the power supply protection module, the communication interface is connected to the monitoring signal output end of the communication module, and the test interface is connected to the monitoring signal input end of the insulation monitoring module.

[0023] In a possible implementation manner, the power supply protection module includes an AC air switch, the lightning protection module includes an AC power lightning arrester, the insulation monitoring module includes an insulation monitor, the indication module includes two indicator lights, and the fuse module includes a fuse.

[0024] In a possible implementation manner, the number of fuses is two, and the fuses are installed on the rail through a fuse mounting base.

[0025] In a possible implementation manner, the cabinet is made of cold-rolled galvanized steel plate.

[0026] In a possible implementation manner, the cabinet is made of 316L stainless steel.

[0027] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

[0028] The embodiments of the present invention provide a power supply protection module for a large generator insulation performance monitoring device, which connects and bears the external AC power supply for the device and inputs the AC power to the lower-level module. When faults such as overload, short circuit, and undervoltage occur in the external power supply circuit, it can realize the functions of automatic tripping and rapid circuit breaking, thereby protecting the device. The lightning protection module connects and bears the AC power input by the power supply protection module and outputs alternating current to the lower-level AC-DC power module and insulation monitoring module to supply power to the lower-level modules. The lightning protection module is mainly used for Class C protection of the power distribution system to protect electrical and electronic equipment from the influence of lightning electromagnetic pulse induced voltage, operation transients, and resonant overvoltage. The insulation monitoring module measures the insulation resistance values of the three paths of the generator stator winding to the ground, the rotor winding to the ground, and the stator winding to the rotor winding. Among them, the measurement channels of the stator winding to the ground and the rotor winding to the ground are connected to the fuse module. The measurement data of the insulation monitoring module is input to the communication module. The fuse module is used to provide protection for the insulation monitoring module to avoid voltage overload damage or even damage to the insulation monitoring module caused by the generator winding circuit. The AC-DC power module converts alternating current into constant direct current. This device solves the problem that neither the on-line monitoring technology nor the off-line measurement method in the prior art can meet the requirements of generator insulation condition monitoring. This device mainly monitors the insulation performance of large generators. This device can be conveniently applied to industrial equipment to inspect and monitor generators, improve the working reliability of generators, and ensure the normal operation of generators. Description of the Drawings

[0029] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 It is a schematic diagram of the principle of the large generator insulation performance monitoring device provided by the embodiment of the present utility model.

[0031] Figure 2 It is a schematic diagram of the structure of the large generator insulation performance monitoring device provided by the embodiment of the present utility model.

[0032] Reference numerals: 1 - cabinet; 2 - power supply protection module; 3 - lightning protection module; 4 - AC / DC power module; 5 - insulation monitoring module; 6 - communication module; 7 - indication module; 8 - insurance module; 9 - guide rail; 10 - mounting base plate. Detailed implementation manners

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, rather than all, of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present utility model.

[0034] In the description of the embodiments of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model. The terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. In addition, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0035] Such as Figure 1 and Figure 2As shown in the figure, the large generator insulation performance monitoring device provided by the embodiment of the present utility model includes a power supply protection module 2, a lightning protection module 3, an ACDC power supply module 4, an insulation monitoring module 5, a communication module 6, and an insurance module 8;

[0036] The input end of the power supply protection module 2 is connected to the output end of an external AC power supply, the output end of the power supply protection module 2 is connected to the input end of the lightning protection module 3, and the output end of the lightning protection module 3 is connected to the input end of the ACDC power supply module 4 and the power supply end of the insulation monitoring module 5;

[0037] The output end of the ACDC power supply module 4 is connected to the power supply end of the communication module 6, the monitoring signal output end of the insulation monitoring module 5 is connected to the monitoring signal input end of the communication module 6, and an insurance module 8 is provided on the line of the monitoring signal input end of the insulation monitoring module 5.

[0038] It should be noted that the power supply protection module 2 connects and bears the external AC power supply that powers the device, and inputs the AC power to the lower-level module. When faults such as overload, short circuit, and undervoltage occur in the external power supply circuit, it can achieve the functions of automatic tripping and rapid circuit breaking, thereby protecting the device.

[0039] The lightning protection module 3 connects and bears the AC power input by the power supply protection module 2, and outputs alternating current to the lower-level ACDC power supply module 4 and insulation monitoring module 5 to supply power to the lower-level modules. The lightning protection module 3 is mainly used for Class C protection of the power distribution system, and is used to protect electrical and electronic equipment from the influence of lightning electromagnetic pulse induced voltage, operation transients, and resonance (<100 μs) overvoltage.

[0040] The insulation monitoring module 5 measures the insulation resistance values of the three paths of the generator stator winding to the ground, the rotor winding to the ground, and the stator winding to the rotor winding. Among them, the measurement channels of the stator winding to the ground and the rotor winding to the ground are connected to the insurance module 8. The measurement data of the insulation monitoring module 5 is input to the communication module 6.

[0041] The communication module 6 is composed of a serial port Ethernet server. The serial port Ethernet server converts the RS-232 / 485 / 422 serial port into a TCP / IP network interface, realizing the bidirectional transparent transmission of data between the RS-232 / 485 / 422 serial port and the TCP / IP network interface; enabling serial port devices to immediately have the function of a TCP / IP network interface and connecting to the network for data communication, greatly expanding the communication distance of serial port devices. The power supply of the communication module 6 is provided by the ACDC power supply module 4. It receives the RS-485 measurement data of the insulation monitor, converts the data, and sends it as a TCP / IP data packet through the network, and then transmits it to a network application program on the Ethernet, such as a monitoring server. The insurance module 8 is used to provide protection for the insulation monitoring module 5 to avoid voltage overload damage to the generator winding circuit and even damage to the insulation monitoring module 5.

[0042] The insurance module 8 is connected to the 5 measurement channels of the insulation monitoring module by high-voltage cables. The ACDC power module 4 converts alternating current into constant direct current.

[0043] This device solves the problem that neither the online monitoring technology nor the off-line measurement method in the prior art can meet the monitoring requirements of the insulation condition of the generator. This device mainly monitors the insulation performance of large generators. This device can be conveniently applied to industrial equipment to inspect and monitor generators, improve the working reliability of generators, and ensure the normal operation of generators.

[0044] In this embodiment, an indication module 7 connected to the insulation monitoring module 5 is further included.

[0045] It should be noted that the ACDC power module 4 only provides the positive power supply for the indication module 7. The insulation monitoring module 5 provides the negative power supply for the indication module 7 through the internal indication relay. The indication module 7 includes two LED metal indicating lights. At the same time, according to different working states, the indication relay conducts and cuts off the negative power supply to control the supply voltage of the indication module 7 and indirectly control the on and off of the indicating lights to indicate the working state of the device. Among them, one indicating light is always on to indicate that the device is in a normal working state, and the other indicating light is always on to indicate that the device is in a measurement state.

[0046] In this embodiment, a cabinet 1 is further included. The cabinet 1 includes a cabinet body and a cabinet door connected to each other, and a lock body is arranged on the cabinet door;

[0047] An installation bottom plate 10 is arranged at the bottom inside the cabinet, and a guide rail 9 is arranged on the installation bottom plate 10;

[0048] The power supply protection module 2, the lightning protection module 3, the ACDC power module 4, the insulation monitoring module 5, the communication module 6 and the insurance module 8 are all installed on the guide rail 9 through buckles, and the indication module 7 is installed on the outer wall of the cabinet;

[0049] Power supply interfaces, communication interfaces and test interfaces are arranged on the side wall of the cabinet body. The power supply interface is connected to the input end of the power supply protection module 2, the communication interface is connected to the monitoring signal output end of the communication module 6, and the test interface is connected to the monitoring signal input end of the insulation monitoring module 5.

[0050] It should be noted that the settings of the guide rail 9 and the buckles facilitate the maintenance and repair of the power supply protection module 2, the lightning protection module 3, the ACDC power module 4, the insulation monitoring module 5, the communication module 6 and the insurance module 8. The settings of the power supply interface, the communication interface and the test interface facilitate the connection of external AC power supply, monitoring server and generator. A bracket for fixing and installing the cabinet 1 is also arranged at the bottom of the cabinet body.

[0051] In this embodiment, the power supply protection module 2 includes an AC air switch, the lightning protection module 3 includes an AC power lightning arrester, the insulation monitoring module 5 includes an insulation monitor, the indication module 7 includes two indicator lights, and the fuse module 8 includes fuses.

[0052] In this embodiment, the number of fuses is two, and the fuses are installed on the rail 9 through fuse mounting seats.

[0053] It should be noted that the rail 9 adopts the TS35 standard rail. There are openings provided on the side wall of the cabinet body, and the indicator lights are installed in the openings. The fuse module 8 uses a total of two fuses and two fuse mounting seats.

[0054] The cabinet 1 serves as the carrier of the device, centrally combines and loads various electrical or electronic devices, cables, mechanical parts and components required by the device; and has the properties of anti-vibration, anti-shock, corrosion resistance, dust prevention, and waterproofing, etc., in order to ensure the stable and reliable operation of the device. The main function of the fuse set in the circuit is to safely and reliably cut off when a circuit failure occurs, so as to provide protection for each discrete component or the entire circuit.

[0055] The power supply protection module 2 is a small standard AC air switch, with a 2P pole number, a C-type tripping type, and a rated current of 33A; the lightning protection module 3 is an AC power lightning arrester, with a working voltage of AC 220V; the ACDC power module 4 is an AC 220V to DC 24V power module.

[0056] The insulation monitor uses the DC injection method to measure the insulation of the generator winding, etc. The test voltage is DC 500V. The instrument is interlocked with the generator circuit to automatically withdraw the insulation monitor from monitoring and separate from the power grid when the generator is running. When the generator stops, the insulation monitor automatically starts to detect the insulation between the generator stator winding and the ground, the rotor winding and the ground, and between the stator winding and the rotor winding. The power supply voltage of the insulation monitor is 85 - 265V AC, and it uses the Modbus protocol and RS-485 interface to output communication data externally. The insulation monitor provides multiple measurement channels to connect to the generator stator and rotor windings.

[0057] The fuse module 8 uses high-voltage cables to connect outside the cabinet 1 to the measuring points of the generator stator and rotor windings.

[0058] For the indication module 7 of the present utility model, the light-emitting color is red, and it is installed in the opening on the side wall of the cabinet 1. Among them, the upper indicator light is always on to indicate that the device is in a normal working state, and the lower indicator light is always on to indicate that the device is in a measuring state. The indication relay conducts and breaks the power supply negative pole according to the different working states of the insulation monitor to control the supply voltage of the indicator light, and indirectly controls the on and off of the indicator light to indicate the working state of the device.

[0059] In this embodiment, the cabinet 1 is made of cold-rolled galvanized steel sheet.

[0060] In this embodiment, the cabinet 1 is made of 316L stainless steel.

[0061] It should be noted that the cabinet 1 made of 316L stainless steel is applied to the offshore wind turbine and can meet the requirements of offshore salt spray corrosion prevention.

[0062] In this embodiment, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced by the present invention.

Claims

1. A large generator insulation performance monitoring device, characterized in that: It includes a power supply protection module (2), a lightning protection module (3), an ACDC power supply module (4), an insulation monitoring module (5), a communication module (6) and a fuse module (8); The input end of the power supply protection module (2) is connected to the output end of the external AC power supply, the output end of the power supply protection module (2) is connected to the input end of the lightning protection module (3), and the output end of the lightning protection module (3) is connected to the input end of the ACDC power supply module (4) and the power supply end of the insulation monitoring module (5); The output end of the ACDC power supply module (4) is connected to the power supply end of the communication module (6), the monitoring signal output end of the insulation monitoring module (5) is connected to the monitoring signal input end of the communication module (6), and the insurance module (8) is arranged on the line of the monitoring signal input end of the insulation monitoring module (5).

2. The large generator insulation performance monitoring device according to claim 1 is characterized in that: It also includes an indication module (7) connected to the insulation monitoring module (5).

3. The large generator insulation performance monitoring device according to claim 2 is characterized in that: Also included is a cabinet (1), the cabinet (1) comprising a cabinet body and a cabinet door connected to each other, the cabinet door being provided with a lock body; A mounting base plate (10) is provided at the bottom of the cabinet, and a guide rail (9) is provided on the mounting base plate (10); The power supply protection module (2), the lightning protection module (3), the ACDC power supply module (4), the insulation monitoring module (5), the communication module (6) and the insurance module (8) are all mounted on the guide rail (9) by means of snaps, and the indication module (7) is mounted on the outer wall of the cabinet.

4. The large generator insulation performance monitoring device according to claim 3 is characterized in that: The side wall of the cabinet is provided with a power interface, a communication interface and a test interface; The power supply interface is connected to the input end of the power supply protection module (2), the communication interface is connected to the monitoring signal output end of the communication module (6), and the test interface is connected to the monitoring signal input end of the insulation monitoring module (5).

5. The large generator insulation performance monitoring device according to claim 3 is characterized in that: The power supply protection module (2) includes an AC air switch, the lightning protection module (3) includes an AC power supply lightning arrester, the insulation monitoring module (5) includes an insulation monitor, the indication module (7) includes two indicator lights, and the insurance module (8) includes a fuse.

6. The large generator insulation performance monitoring device according to claim 5 is characterized in that: The number of the fuses is two, and the fuses are mounted on the guide rail (9) via a fuse mounting seat.

7. The large generator insulation performance monitoring device according to claim 3 is characterized in that: The cabinet (1) is made of cold-rolled galvanized steel plate.

8. The large generator insulation performance monitoring device according to claim 3 is characterized in that: The cabinet (1) is made of 316L stainless steel.

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